Major Changes Since 1.13

Per-window private-browsing

If your add-on uses private browsing and is built with an earlier version of the SDK, it must be repacked with this version to be usable on Firefox 20. We are aiming to automate repacks of as many add-ons as possible, and will contact the authors of AMO-hosted add-ons to let them know if they need to repack.

Due to a platform bug, if you update your code to use the new private browsing APIs (rather than just repack your code with the new SDK version), then your add-on will not be able to use the panel module.

If an add-on is uninstalled while it's disabled, it's not notified of uninstall. If the add-on needs to do some special cleanup on uninstall, like removing persistent storage such as a file, this won't be possible if it has been disabled.

By default, widgets are placed on the add-on bar, and given a height to match the height of that bar. If the user moves the widget to a different toolbar, and that toolbar has a different height, the widget's height is not updated accordingly.